You have a plenty of choice in Alfa garages in this area.
1. You can go to ProAlfa in Watford and you can find some information and opinions about them on here. To be honest, I have never been there.
2. A little farther to the north is AutoLusso, where I usually go ther to do any major service. It takes you about 30 min to drive to them. Call Ned and his mechanics.
3. You can go to Jamie in Royston, Alfaworkshop. He has very good opinion on here and they've done a few things on my Gtv.
4. The fourth choice would be Veloces in New Barnet. They are good but not the cheapest one.
5. Or any main Alfa dealer (one is in Hemel Hempstead).

try giving the injectors a good clean with some redex or the like, also just to help that little bit i filled mine with BP ultimate and ran it on that for a couple of weeks leading up to the test and had that in for the test as it al;legedly burns slightly cleaner than standard fuel

Going to try a minor service first with air filter & new plugs then perhaps check the Coolant temp sensor and AFM. If that's not enough I suppose will have to start thiningk about the cat. The lambda is switching as went for a re-try on the analyzer after a blast and engine temps up, you can see its trying to pull the co down but just cant. I Wonder if the injectors have a bad spray pattern or perhaps leaking? Bit of a bummer as it only needed brakes sorted for the rest of the Mot! Anyhow its burning rich, almost like a carb with choke stuck on!

Is your car getting up to temperature, just below 90 degrees? If it's around the mid marker you will need to change the thermostat, as otherwise it will run rich. I've changed mine last week, so I know that's not the problem on mine. Nothing else wrong on mine, which as you say is a bummer.

It only gets up to temperature in town driving, on the run it never makes 90 but sits around the mid mark, put that down to winter temp's as I have never had a GTV (or any car with a specific centigrade indicator!) so I will change the stat, cheers alfapush for that. It could be a combination of things I suppose, I will do a process of elimination (cheapest first) I was looking at the FiatECUscan software (now with the older GTV'S ECU'S catered for) ,that seems very interesting, it could possibly pinpoint any other, related problems. Of course I would need to learn how to use it first! . Will put some injector cleaner through the system but I need to find out why she's burning rich it could be that the cat has been damaged with excess vapour, as the exhaust gas stinks of petrol! As for running ok, sometimes & not very often, upon starting she dies if I dont keep the revs up for a while. ie wont idle. will keep at it and keep all posted as to how I get on as it could be usefull for someone in the future.

Fiat ecu scan is easy to use and you can download the free version easily(although not everything is on this). You will need to buy a cable,to connect the laptop to the car. I bought and recommend the switched cable, from ebay, you can buy an unswitched cable but you will need to modify it, to use it, I didn't want the hassle. I bought the stat from Rapid parts on ebay about £40, easy to fit and you will notice a difference staight away. There is a very interesting site called Just Lambda it fully explains then in's & out's of what it does, faults, fitting, good pics etc. It also states they should be checked/replaced every 30,000 miles. With regard to idle problems, that might be the idle control activator, it sits on top of where the throttle cable connects to and the hose at the end of the airtake system. The are several links on here that you can check out.

Thanks, found a vacuum hose on the fuel pressure regulator well split, dont know how much that would influence the enrichment?

A split vacuum hose could well mean failed emissions as the vacuum hose assists in opening the regulator to bypass fuel to the tank. Repair this and service your car while replacing the air filter. Hopefully that's all that will be required

The reason being the injectors control the amount of fuel going in, all the regulator does is control fuel pressure at the fuel rail.

If you were to increase the fuel pressure (If the valve was malfunctioning) the Lambda sensor should detect the overly rich mixture and shorten the injector duration to compensate.

High CO is caused by partly burned fuel from a rich mixture, or a mixture that isn't being ignited properly.

For me that either points at the Lambda, MAF or spark plugs. If the car otherwise seems to drive ok it probably isn't the MAF.

One way of checking for a slow switching lambda is to get the engine warm, then with the car stationary attempt to hold the revs at 2000rpm. If the needle on the rev counter moces side to side then the Lambda is probably faulty.